@article{oai:repo.qst.go.jp:00043603,
 author = {Zhang, Hong and Yoshikawa, Kyosan and Tamura, Katsumi and Sagou, Kenji and Mei, Tian and Suhara, Tetsuya and Kandatsu, Susumu and Suzuki, Kazutoshi and Tanada, Shuji and Tsujii, Hirohiko and 張 宏 and 吉川 京燦 and 田村 克巳 and 佐合 賢治 and 須原 哲也 and 神立 進 and 鈴木 和年 and 棚田 修二 and 辻井 博彦},
 issue = {9},
 journal = {Skeletal Radiology},
 month = {Sep},
 note = {Objective Chordoma is a rare malignant bone tumor that arises from notochord remnants. This is the first trial to investigate the utility of 11C-methionine(MET) positron emission tomography(PET) in the imaging of chordoma before and after carbon-ion radiotherapy(CIRT).
Design and patients Fifteen patients with chordoma were investigated with MET-PET before and after CIRT and the findings analyzed visually and quantitatively. Tumor MET uptake was evaluated by tumor-to-nontumor ratio(T/N ratio).
Results In 12(80%) patients chordoma was clearly visible in the baseline MET-PET study with a mean T/N ratio of 3.3±1.7. The MET uptake decreased significantly to 2.3±1.4 after CIRT(P＜0.05). A significant reduction in tumor MET uptake of 24% was observed after CIRT. Fourteen (93%) patients showed no local recurrence after CIRT with a median follow-up time of 20 months.
Conclusion This study has demonstrated that MET-PET is feasible for imaging of chordoma. MET-PET could provide important tumor metabolic information for the therapeutic monitoring of chordoma after CIRT.},
 pages = {524--530},
 title = {Carbon -11-methionine positron emission tomography imaging of chordoma},
 volume = {33},
 year = {2004}
}